Rational Selection of Hole Contacts with an Organic Light-Emitting Diode Industry p-Dopant for Fully Vacuum-Processed Perovskite/Silicon Tandems

Translating perovskite/silicon tandems to fully vacuum-based manufacturing requires vacuum-compatible p-doped hole contacts, yet clear selection criteria for doped hole-transport materials (HTMs) remain underdeveloped compared with C60-based electron contacts. Here, we report a fully vacuum-processed perovskite/silicon tandem reaching 29.1% power conversion efficiency, among the highest reported for tandems with fully vacuum-deposited perovskite top cells, enabled by transferring the organic light-emitting diode (OLED)-industry p-dopant NDP-9 and an evaporable arylamine HTM into the perovskite stack. Comparing TaTm, Spiro-TTB, and TAPC shows that contact selection does not follow apparent host–dopant interaction strength derived from theoretical calculations or conventional optical, vibrational, and photoemission spectroscopies. Instead, device-level charge extraction and recombination metrics identify NDP-9-doped TaTm as the most effective contact, also yielding 20.0% in a single-junction 1.70 eV wide-bandgap cell. These results point to transport-based screening as a practical route to selecting vacuum-compatible doped hole contacts.